Flexible and adjustable ruler for drawing curves.



No. 632,240. Patented Sept. 5, I899.

G. P. CLARK. V I FLEXIBLE AND ADJUSTABLE BULER FflB DRAWING CURVES.

(Application filed May 28, 1898;)

(No Model.)

Ni n STATES ATENT GORDON PATON CLARK, OF LONDON, ENGLAND.

SPECIFICATION forming part of Letters Patent No. 632,240, dated September 5, 1899. Application filed May 26, 1898. Serial No. 681,823. tNo model.)

T0 aZZ whom, it may concern.-

Be it known that I, GORDON PATON CLARK, a subject of the Queen of Great Britain, and a resident of 10 Lansdowne road, London, W., England, have invented certain new and useful Improvements in or Relating to Flexible and Adjustable Rulers for Use in Drawing Curves, of which the following is a specification.

This invention relates to an improved flexible and adjustable ruler for use in drawing curves.

In the annexed drawings, Figure 1 is a plan, and Fig. 2 an elevation, of the ruler. Fig. 3 is a cross-section thereof on line 3 3, looking to the left.

A strip of flexible and resilient material is provided at or near each end with a loop or hook B O in such a manner that the user by placing his fingers and thumb in such loops or hooks can move the ends of the strip A or draw them toward each other, so as to curve the strip more or less or modify the shape of its curve. In order to have means for further modifying the curve so given, I provide in suitable guides attached to the strip A, preferably in guides or holes in one of the hooks or loops themselves, a sliding rod D to form a rigid abutment adjustable lengthwise of the ruler in order that on or after the commencement of the bending of the ruler by the user the said device may form an abutment modifying the curve of the flexible strip A, which is used as the ruling-surface. Since the rod D moves with friction in its guidenamely, the guiding-holes through which it passes in the finger-loop-and the curvature of the strip A tends to press it sidewise, thus increasing the friction, the rod D is not displaced by the pressure exerted on it by the strip A; but it may be readily adjusted by the one hand of the operator, while the other holds or curves the ruler by use of the fingerloops, as before described.

In applying to the strip A of flexible and resilient material improved means for retaining the same for an indefinite period at the curvature to which it has been adjusted I attach a cord F to a suitable loop or the like at or near one end of the stripfor instance, to the loop B-and at or near the other end of the strip A, I provide the other loop or the like 0 with means by which the cord may be held firmly. The loops B O serve as means by which the strip A may be adjusted to the curvature desired by the fingers of the draftsman, while the cord F is drawn taut and secured so as to hold the strip in the curve given to it. To fasten the cord, I may use a tapering recess or elongated hole G in the loop 0, toward the narrow end of which the cord F may be drawn when taut, so as to nip the cord and so secure it.

What I claim, and desire to secure by Letters Patent, is-

1. The combination with a flexible strip A of two fin ger-holds attached to said strip at a distance apart and an abutment movable longitudinally of the strip between said fingerholds substantially as set forth.

2. The combination with a flexible strip A of two finger-holds B and 0 attached to said strip at a distance apart, a rod D having sliding bearing in one of said finger-holds and an abutment E on said rod for the purpose set forth.

3. The combination with a flexible strip A of two finger-holds attached to said strip at a distance apart, a cord attached to one of said finger-holds and means for adjustably attaching said cord to the other finger-hold.

4. The combination of a flexible strip, two finger-holds attached respectively near the two ends of the strip, a cord attached near one end of the strip and means for adj ustably attaching said cord near the other end of said strip for the purpose set forth.

In witness whereof I have signed this specification in the presence of two witnesses.

GORDON PA'ION CLARK.

lVitnesses:

A. J. HADDAN, O. Roonn. 

